Lead pointer



G. A. MOURRA Jan. 18, 1966 LEAD POINTER 2 Sheets-Sheet 1 Filed Jan. '7,1964 INVENTOR. 6502 25 A. Moulzaa G. A. MOURRA Jan. 18, 1966 LEADPOINTER 2 Sheets-Sheet 2 Filed Jan. 7, 1964 INVENTOR. sol-acres A.MouaaA ATTORNEYS United States Patent 3,229,670 LEAD POINTER Georges A.Mourra, R0. Box 1282, Blvd. JN-Jacques,

This invention relates to motor-driven means for sharpening the leads ofpencils and mechanical equipment normally used by draftsmen, engineers,artists and architects. More specifically, the instant invention isdesigned to provide an automatic motor-driven pencil sharpener which maybe used by any craftsman to form a fiat, chiseled point and wedge pointson the leads of the equipment it is proposed to use.

One of the primary objects of this invention is to provide power-drivenmeans for sharpening the leads of mechanical pencils into any desiredconfiguration.

A further object of this invention is to provide powerdriven means forsharpening the leads of mechanical pencils while, at the same time,providing means for pre venting the graphite dust from coming intocontact with the users hands.

A further object of this invention is to provide a device of the typegenerally described above which will constantly produce the desired leadpoint efiiciently and which is serviceable over a long period of timewithout necessitating any replacement parts.

This invention contemplates, as a further object thereof, the provisionof a power-driven automatic pencil sharp ener as referred to supra, thesharpener being noncomplex in construction and assembly, inexpensive tomanufacture and maintain, and which is durable in use.

Other and further objects and advantages of the instant invention willbecome more manifest from a consideration of the following specificationwhen read in conjunction with the annexed drawings, in which:

FIGURE 1 is a perspective view of a power-driven automatic pencilsharpener constructed according to this invention;

FIGURE 2 is an enlarged detail, cross-sectional view, FIGURE 2 beingtaken substantially on the vertical plane of line 22 of FIGURE 1,looking in the direction of the arrows;

FIGURE 3 is a detail cross-sectional view, FIGURE 3 being takensubstantially on the vertical plane of line 3-3 of FIGURE 2, looking inthe direction of the arrows;

FIGURE 4 is a detail cross-sectional view, FIGURE 4 being takensubstantially on the plane of line 4-4 of FIGURE 2, looking in thedirection of the arrows;

FIGURE 5 is a fragmentary bottom plan view, partly in cross-section,FIGURE 5 being taken substantially on the horizontal plane of the line5-5 of FIGURE 2, looking in the direction of the arrows;

FIGURE 6 is a fragmentary detail cross-sectional view of the electricswitch means, FIGURE 6 being taken substantially on the vertical planeof line 6-6 of FIGURE 3, looking in the direction of the arrows;

FIGURE 7 is a bottom plan view of the cover member, partly incross-section, FIGURE 7 being taken substantially on the horizontalplane of line 7-7 of FIGURE 2, looking in the direction of the arrows;

FIGURE 8 is a fragmentary side elevational view, partly broken away andillustrating the utility of the sharpener to form a chisel-type edge onthe lead of a mechanical drafting instrument; and

FIGURE 9 is a perspective schematically illustrating the wiring diagramutilized to energize the motor for driving the automatic pencilsharpener.

Referring now more specifically to the drawings, ref- 3,229,670 PatentedJan. 18, 1966 ice erence numeral 10 designates, in general, apower-driven automatic pencil sharpener constructed in accordance withthe teachings of this invention. The sharpener 10 is seen to comprise aself-contained unit which includes a substantially hollow rectangularhousing 12 preferably formed of plastic material, but other desirablesubstantially rigid materials may be employed. Housing 12 is formed witha normally horizontal substantially rectangular base wall 14 from theperipheral marginal edges of which rise connected and opposed pairs ofsubstantially rectangular and parallel sidewalls 16, 18 and 20, 22,respectively. The walls 16, 18, 20, 22, at each corner formed thereby atthe junction of each adjacent pair of sidewalls is provided with aninwardly-extending integrally-formed vertically-elongated andinternally-threaded boss 24 adjacent the upper ends thereof. The upperends of the sidewalls 16, 18, 20 and 22 are spanned and support thereona substantially rectangular closure member 26 comprising a substantiallyrectangular top wall 28 from which depend an opposed pair ofsubstantially rectangular sidewalls 30, 32 and an opposed pair ofsubstantially rectangular parallel sidewalls 34, 36, the latter beinginset at 36A and connected therewith by means of a V- shaped flange 38(see FIGURE 8) which extends between the sidewall 36- and the insetsidewall 36A at substantially right angles relative thereto. The flange38 includes the depending and converging arms 40, 42, and to the arm 42is secured a substantially rigid rectangular backing member 44'for aplurality of bristles 46 of a cleaning brush designated generally byreference numeral 48. Connected with the inset sidewall 36A andprojecting laterally and outwardly from the lowerlongitudinallyextending marginal edge thereof is an elongatedsubstantially rectangular flange 50 having an opening 52 formed thereinadjacent its inner end. As is seen in the drawings, the flange 50 has anupper planar surface 50A which tapers downwardly toward the opening 52.The flange 50 is seen to continue inwardly in an elongated substantiallyrectangular rig 50B until it integrally joins with the sidewall 36 (seeFIGURE 1).

The upper ends of the sidewalls 16, 18, 20 and 22, and the lower ends ofthe sidewalls 30, 32, 34, 36, and the flange 50 together with its rib50B are rabbeted at 54 throughout their continuous peripherie to permitinterfitting and mating therebetween.

At the junction of adjacent pairs of sidewalls 30, 32, 34 and of theflange 50 with the sidewall 30, the inner corners thereof are formedwith integral inwardly-extending hollow bosses 56 which are adapted tobe aligned with the bosses 24 whereby screws 58 may be passed throughthe bosses 56 for threaded engagement with the bosses 24, whereby thecover member 26 may be releasable secured to the upper ends of thesidewalls 16, 18, 20 and 22.

The top wall 28 is provided with an elongated substantially rectangularslot 60 which extends inwardly from the sidewall 32 toward the sidewall30 and terminates proximate to, but spaced from the latter. Theoppositelydisposed laterally-spaced and substantially parallel sidewalls62, 64 are formed with inwardly-extending longitudinal grooves 66, 68,respectively, in which are disposed elongated substantially rectangularelectrical current conducting bars 70, 72. The bars 70, 72, at a pair ofadjacent ends thereof are formed with laterally-projecting and divergingcentrally-tapped flanges 74, 76, respectively, which seat in cut-outs78, projecting laterally from the walls 62, 64 adjacent the outer openend of the slot 60.

Reference numeral 82 denotes an elongated substantially rectangularcarriage having a depending integral pad 84 at one end thereof. As isseen in the drawings, the pad 84 is formed with an arcuate abutment end86 which is adapted for engagement with the arcuate end 88 of the slot60 when the carriage 82 is moved in the direction of the'arrow shown inFIGURE 7, thereby limiting the movement of the carriage 82 in onedirection.

Reference numeral 83 designates a metallic U-shaped switch having abight section 83A from which project a pair of arms 83B, 830, the latterbeing adapted to slide between the bars 70, 72 and out of contacttherewith to make and break an electrical circuit to be described.

:The switch 83 is adapted to embrace, and is secured to,

the sides and an end of the carriage 82.

A normally vertically-extending substantially hollow boss is indicatedat 90, the boss 90 including a substantially hollow cylindrical wall 92which projects upwardly from the carriage 82 at the pad end thereof, andwhich is 96, 98 spaced 180 apart. As is seen in FIGURES 1 to 3,inclusive, the boss 92 is shown as receiving the lead end of amechanical pencil 100, the knurled finger- :grasping end 102 beingsubstantially embraced by the cylindrical casing 92 while the conicalchuck end 104 is surrounded by the conical casing 94 with the lead 106engaged between and being supported by the tines 96, 98.

Reference numerals 107 designates a pair of elongateddownwardly-converging, integrally-formed substantially rectangularhanger brackets, the upper ends of the brackets each having an offsetend 108 secured to the underside of the top wall 28 by screws 110. Theother or lower ends of the brackets terminate in brushes 112 disposedadjacent the inner end of the slot 60 in the path of movement of thelead 106 and tines 96, 98 as the carriage 82 is reciprocated in the slot60. Reference numeral 114 denotes a cylindrical bearing seat formed inthe top wall 28 adjacent a side thereof, the opening 114 receivingtherein a bearing 116 of conventional design. Any conventional bearingretention means may be employed to retain the bearing 116 within itsseat 114. The bearing 116 is Welded at 118 to the hub 120 of a dependingsprocket gear 122, see FIGURES 1, 2 and 5.

Surrounding the bearing seat 114 at the circumferential marginal edgethereof is an internally-threaded collar 124 secured to'the upper sideof the top wall 28 by screws 126. Reference numeral 128 refers to ahousing including a cylindrical sidewall 130 having a closure wall 132at one end thereof and an opposed externally-threaded open end. Theclosure wall 132 is centrally-apertured at 134 and the cylindricalsidewall 130 is provided with diametricallyopposed substantiallyrectangular axially-extending slits 136. As is seen in FIGURE 2, theopen threaded end of the housing 128 is threaded intothe collar 124.

Disposed within-and axially-aligned with the housing 128 is anaxially-elongated hollow cylindrical member 138 having anoutwardly-extending cylindrical flange 140 which forms a first bearingrace at the upper end thereof. As is clearly seen in FIGURE 2, the innerside of the sidewall 138 is substantially circular in transversecrosssection over a major portion of its length, but the lower endportion 142 tapers downwardly and inwardly to take a hollow invertedfrusto-conical configuration. The cylindrical member 138 carries awasher 144 loosely thereon adjacent the flange 140 to forma secondbearing race. The cylindrical member 138 is keyed to the hub 120 bymeans of a pair of diametrically-opposed keys 146, the upper ends of thelatter abutting the washer 144. Surrounding the cylindrical member 138axially thereof is a helicoidal spring 148 under compression. Theuppermost one of the convolutions of the spring 148 abuts the washer 144while the lower end thereof abuts the bearing and hub assembly 116, 120.The spring 148 constantly biases the cylindrical member 138 for movementin a direction away from the hub 120. A flat cylindrical plate 150'isjuxtaposed with respect to the closure wall 132 and forms a thirdbearing race.

The plate 150 is centrally-apertured as at '152,'the aperture 152 beingconcentric with respect to the aperture 134. As shown in FIGURES 1, 2and 3, a pair of substantially rectangular levers 149 projectdiametrically and laterally away from the plate 150 and through theslots 136. Bearings 154 are inserted between the flange and washer 144,and between the flange 140 and the plate to serve a function to bedescribed.

Shown in FIGURES 1 and 2 are a plurality of leaf springs 156 having oneof their respective ends fixedly secured to the upper flanged end of thecylindrical member 138 and the other ends thereof extend through theaperture 150 and the opening 134 formed in the closure wall 132 andproject beyond the latter. Each of the leaf springs 156 is formed,intermediate their respective ends, with an outwardly-bowed portion 157to serve a function to be described infra. 7

Reference numeral 158 indicates an elongated cylindrical rod having oneof its ends threaded into one of the levers 149, the other end thereofbeing reciprocable through the collar 124 and the top wall 28. To thelower or the aforementioned other end of the rod 158 is secured a bightmember 160 (see FIGURES 2 and 7) from the opposed ends of which depend apair of downwandly-diverging prongs 162, respectively, (see FIGURES 3and 7) the prongs 162 serving a purpose to be described.

Adjacent to but spaced inwardly from the prongs 162 is a bracket 164connected to the top wall 28 as by screws 166. The bracket 164 includesa subtended bight element 168 on which are pivotally connected on apivot pin 170 a pair of arms 172. The arms 172 are crossed, and arepivotally connected intermediate their respective ends inscissors-fashion to provide arm extensions 174. A brush 176 is mountedon the outer terminal end of each arm 172, and the prongs 162 areadapted to engage the remotely-disposed sides of the arm extensions 162,whereby, as the rod 158 moves downwardly, the arms 172 are caused tomove toward each other to bring the brushes 176 into confrontingrelation.

As shown, the cylindrical member 138 receives the major portion of theknurled finger-gripping section 178 of a mechanical pencil 180. Thechuck end 182 thereof is, of course, seated in the invertedfrusto-conical portion 152.

An inverted Y-shziped yoke 184 has its stem 186 fixedly secured to theunderside of the top wall 28. The depending arms 188, 190 engage onopposite sides of the stem 192 of a U-shaped yoke 194. The 'stem 192 ispivotally connected intermediate its ends to the arms 188, 190 by apivot pin 196. The yoke 194 is formed of an electrical conductingmaterial and includes switch arms 198 which project laterally from eachend of a crossbar 200, respectively, to which the stem 192 is alsoconnected. The outer end of the stern 192 is connected with one end of arod 202 of electrical insulating material having a wear ball 204 at itsouter end. As is seen in the drawing, the wear ball 204 is disposed inthe downward path of movement of one of the prongs 162 whereby uponengagement of the prong 162, the switch arms 198 pivot upwardly as isindicated by the arrow in FIGURE 6. The router ends of the switch arms198 each carries outwardly-facing switch contact points 206.

Fixedly mounted on the top wall 28, as by screws 208, are a pair ofdepending fixed switch arms 210, the switch arms being substantiallyrectangular in configuration and diverging from one another. The switcharms 210 are disposed in the path of movement of the-switch arms 206, asis indicated in dotted lines in FIGURE 6, and when contact is madetherebetween an electrical circuit is established which will bedescribed below.

Fixedly mounted on the base wall 14 is a conventional electric motor 208having its drive shaft (not shown) connected with a conventional gearbox 210 having an output shaft 212 on which is keyed a bevel gear 214.An inverted substantially U-shaped bracket 216'is provided, the bracket216 comprising a'bight portion 218 from each end of which depends a sidearm 220 the latter being secured to the sidewalls 16, 20 as by screws222.

Reference numeral 224 denotes a second bevel gear in mesh with the firstbevel gear 214, the bevel gear 224 having a hub 226 integral therewithwhich bears against the underside of the bight 218. The bight 218 isapertured to receive therethrough the lower end of a shaft 228 which iskeyed, or otherwise secured within the hub 226. Reference numeral 230denotes a spur gear having a hub 232, the hub 232 bearing against theupper side of the bight 218. Thus, it is seen that the shaft 228 islocked against axial shifting movement. The central portion of the shaft228 is squared, as at 234, and the upper end thereof denoted byreference numeral 236 is cylindrical and is housed for rotation within ajournal 238 which depends from the top wall 28. Mounted on the squaredportion 234 of the shaft 228 is a grinding or abrasive wheel 240 havinga top and bottom abrasive surface 242, 244, respectively, asubstantially cylindrical abrasive surface 246 and a frusto-conicalabrasive surface 248.

As is seen in FIGURES 2 and 3, the shaft 228 extends upwardly through anopening 250 formed in the bottom wall 252 of an elongated substantiallyrectangular dust collecting receptacle 254. The dust-collectingreceptacle 254 includes the opposed pairs of substantially rectangularsidewalls 256, 258 which are substantially parallel to one another andwhich rise from the bottom wall 252, and the opposed pairs of sidewalls260, 262 which are also substantially rectangular and extend parallelwith respect one another.

The receptacle 254 is supported over the bight 194 by means of lugs 264which project from the sidewalls 16, 18.

A second shaft 266 has its lower end journaled for rotation within thebight 218, the shaft 266 being reduced at 268 to receive from the grooveformed thereby a lock washer 270. The lock washer 270, as shown in FIG-URE 2, is adapted to bear against the underside of the bight 218.Reference numeral 272 indicates a second spur gear which meshes with thespur gear 230, the second spur gear 272 being keyed, as at 274, to theshaft 266. The shaft 266 extends upwardly from the bight 218 through anopening 276 formed in the bottom wall 252 of the receptacle 254, and onthe upper end thereof is squared, as at 278. The shaft 266 is providedwith a circumferential flange 280 immediately adjacent the lower end ofthe squared portion 278. The squared portion 278 terminates at its outerend in a cylindrical section 282 which, in turn, terminates in a squaredsection 284. Telescoped over the end sections 282, 284 is an elongatedsubstantially hollow cylindrical cap 286 having an internal borecomplementing the sections 282, 284. Thus, the cap 286 is locked to theend section 284 of the shaft 266 and will rotate therewith. The upperend of the cap 286 terminates in a cylindrical projection 288 at a spurgear 290 as keyed thereto for rotation therewith. The spur gear 290 isdisposed within a substantially cylindrical housing 292 having opposedsidewalls 294, 296, a top wall 298, and a bottom wall 300. As is seen inFIGURES 2 and 3, the sidewall 296 is provided with a substantiallyrectangular aperture 302 through which projects a portion of the spurgear 290. The spur gear 290 meshes with the spur gear 122, as shown.

Any suitable means such as screws 304 (see FIGURE 2) may be used tosecure the housing 292 to the top wall 28. In this instance, the screws304 are threaded into the top wall 298.

Mounted on the squared portion 278 of the shaft 266 and supported on theflange 280 is a second abrasive wheel 308. The abrasive wheel 308 issubstantially hollow and includes a centrally-located discoidal member310 which receives the squared portion 278 of the shaft 266, asubstantially cylindrical external abrading surface 312 and an exteriorfrusto-conical abrading surface 314. The inner surface 315 issubstantially frusto-conical in configuration at each side of thediscoidal member 310 with the apex ends thereof facing one another andjoining with the discoidal member 310 substantially at the plane oftheir respective frustums.

Referring now more specifically to FIGURES 7 and 9 of the drawings, anelectric circuit to the motor 208 is schematically illustrated.

Reference numerals 320, 322 indicate wire leads extending from aconventional source of E.M.F. As is seen in FIGURE 9, the lead 320connects with one side of the motor 208, while the other side of themotor connects through wire 324 the flange 76 of the conducting bar 72.Wire 326 has one of its ends also fixedly connected to the flange 76 andits other end fixedly connected to one of the switch arms 210. The otherof the switch arms 210 is connected to one end of the wire 328, and theother end of the wire 328 connects with the flange 74 of the conductingbar 70. As is seen in FIGURE 9, the flange 78 is connected through thewire 322 with the other side of the source The motor 208 may beenergized through either one of two circuits. First of these circuitsincludes the wire 320, motor 208, wire 324, conducting bar 72, theswitch arm 83C, when the U-shaped switch arm 83 is moved into contacttherewith, the bight 83A, the switch arm 83B, the conducting bar 70 andthe wire 322. The circuit is, of course, de-energized when the carriage82 is moved in such direction as to cause the switch arms 83B, 83C tomove out of contact with the conducting bars 70, 72. The second of thesecircuits is energized by depressing the rod 158, causing one of theprongs 162 to engage against the wear head 204 of the yoke 194. Thiscauses the switch arms 198 to pivot upwardly and into engagement withthe fixed switch arms 210. The circuit then reads wire 320, motor 208,wire 324, and wire 326 to one of the switch arms 210 (FIGURE 9). Currentthen passes through one of the switch arms 198, the bight 200 andthrough the other of the switch arms 198. From this point the currenttravels through the other of the switch arms 210, and wires 328, and322, back to the source of The mechanical arrangement of the describedcomponent elements of this invention facilitates the grinding of anydesired surface on the leads of the mechanical pencils 100, 180. Forexample, in order to sharpen the lead 106 flat the abrasive wheels 240,308 are reversed from the position shown in several of the figures ofthe drawings so that the cylindrical surfaces 246, 312 are uppermost,and the mechanical pencil 100 is held in the boss and is pusheddownwardly therein to bring the lead 106 into contact with the tines 96,98. In this position as shown in the drawings, the tines 96, 98 aredisposed between the grinding surfaces of the abrasive wheels 240, 308and since they are smaller than the opposed sides of the lead 106, thelead will be ground flat when the carrier 82 is reciprocated. It isassumed, of course, that the necessary current is supplied to the wires320, 322 so that the motor 208 is energized to drive the wheels 240,308.

The driving of the wheels 24!), 308 is accomplished, of course, throughthe gears 214, 224, the shaft 228, the gear 230, the gear 272, and thecylindrical member 138 is rotated by shaft 266, and the shaft portions278, 282, 284, the cap 286 and the cap end section 296, gear 290, andgear 122.

As the carriage 84 is move-d to its original starting position as isillustrated in FIGURES 1 and 2, the lead 106 engages against thebristles 112 and all graphite is brushed from lead 106 and the pencil isready for use. In restoring the carriage 84 to its original position,contact is broken between the bars 70, 72 and the switch arms 83B, 83C,thereby de-energizing the motor 208.

To give the mechanical pencil leads a chisel configuration, the abrasivewheels 240, 308 are mounted on their respective shafts in the mannerillustrated in the drawings and the mechanical pencil 100' is againinserted in the boss 90, and the carriage 84 is moved forwardly in orderto establish the circuit to the motor 208. The lead 106 is then movedbetween the abrastive wheels 240, 308 and the device is operated asbefore.

In order to provide a pencil lead having a wedge configuration, one ofthe abrasive wheels is turned upsidedown from its position shown in thedrawings, and the same operations are carried out as before.

In using the cylindrical member 138, the mechanical pencil 180 isinserted therein, after which the user exerts pressure on the levers144, forcing the cylindrical member 138 downwardly against the tensionof the spring 148. As the prongs 167. descend, the switch arms 198 arecaused to swing upwardly into contact with the switch arms 210 by virtueof the engagement of the wear head 204 with one of the prongs 162,thereby establishing the motor circuit. The downward movement of thecylindrical member 138 causes the lead 179 to engage against theabrasive inner side 315 of the wheel 308. It will be understood, ofcourse, from the describe-d gearing, that the gear 122 and thecylindrical member 138 rotate in a direction contra to the direction ofthe rotation of the abrasive wheel 308. As the cylindrical memberdescends, the prongs 162. also engage the extension arms 174 causing thearms 172 to move away from each other and draws their respective brushes176 in the same direction.

The downward movement of the cylindrical member 138 causes the bowedportions 157 of the leaf springs 156 to lock under the plate 154,thereby holding the cylindrical member in its grinding position. Thepencil 180 is, of course, released from the fingers of the user as soonas the springs 156 lock under the plate 154 to permit the cylindricalmember to freely rotate.

When the sharpening has been completed, it is only necessary for theuser to release the levers 144, whereby the cylindrical member 138 andthe prongs 162 are alsomoved upwardly under the force of the springs148. As this upward movement takes place, the rod 158 is also movedupwardly, whereby the prongs 162 are disengaged from the wear head 204,permitting the motor circuit to be broken and, simultaneously, the leafspring 175 forces the arms 172 to move toward one another, moving thebrushes 176 into contact with the lead 179. This action is permittedsince the prongs 162 no longer engage the arm extensions 174.

FIGURE 8 ilustrates still another use of this sharpening means whereinreference numeral 400 denotes the leg of a mechanical draftinginstrument, such as the leg of a drafting compass wherein is mounted aconventional drafting lead 402. As is seen in FIGURE 8, the lead 402 isinserted through the opening 52 to engage against the upper end 242 ofthe abrasive wheel 240. When the desired point has been ground, the lead402 may be brushed against the bristles 46.

Having described and illustrated one embodiment of this invention indetail, it will be understood that the same is offered merely by way ofexample, and that the invention is to be limited only by the scope ofthe appended claims.

What is claimed is:

1. A pencil sharpener comprising a substantially hollow rectangularhousing having a base wall, opposed top wall, and pairs of opposedsidewalls, said top wall having an opening extending transverselytherethrough, bearing means disposed within said opening, a spur geardisposed within said housing adjacent said top wall, said spur gearhaving a hub journaled for rotation in said bearings, an elongatedsubstantially hollow cylindrical member having an end thereof fixedlysecured within said hub for rotation therewith, said cylindrical member,at its other end, having a centrally-apertured cylindrical plate.projecting outwardly therefrom, said plate having a pair ofoutwardly-extending diametrically-opposed levers projecting therefrom, awasher mounted on said cylindrical member, said plate and washer beingdisposed on opposite, sides of said flange, a resilient meanssurrounding said cylindrical member and bearing against said washer, andsaid hub, bearings interposed between said washer and said flange andsaid plate, a substantially hollow elongated cylindrical casing having apair of opposed open and closed ends, means connecting said open end ofsaid casing to said top wall at the circumferential marginal edgethereof, said closed end of said casing having a centrally-locatedaperture extending transversely therethrough, said casing having a pairof axially-extending diametrically-opposed substantially rectangularslots formed therein to receive said levers for reciprocation, saidlevers projecting beyond the sidewall of said casing, a shaft mounted onsaid base wall, a substantially hollow abrasive wheel mounted on saidshaft for rotation therewith, and means engaging with said spur gear todrive said abrasive wheel and said cylindrical member.

2. A pencil sharpener as defined in claim 1, wherein the inner side ofsaid hollow abrasive wheel comprises a pair of frusto-conical surfaceswith said frusto-conical surfaces meeting substantially at the plane oftheir respective frustums.

3. A pencil sharpener comprising a substantially hollow rectangularhousing comprising a base wall, opposed top wall, and pairs of opposedsidewalls, said top wall having a slot formed therein extendingtransversely therethrough, a carriage mounted for reciprocation withinsaid slot, said carriage having a substantially hollow upright bossprojecting therefrom, said boss being in open communication with aninverted frusto-conical'casing depending from said carriage and fixedlyconnected thereto, said boss and frusto-conical casing being adapted toreceive a lead pencil therein thelead of which is to be sharpened, aplatform, extending between and fixedly secured to a pair of opposedsidewalls, a pair of vertically-extending shafts having one of theirends journaled for rotation in said platform, an abrasive wheel mountedon each of said shafts for rotation therewith, said abrasive wheelsbeing disposed in close proximity relative to one another, said carriagebeing reciprocable in said slot to move said lead between said abrasivewheels and thereby sharpen the same, a gear on each of .said shaftsadjacent said one ends thereof, said gears being in mesh with eachother, a second gear on one of said shafts, said top wall having anopening extending transversely therethrough, bearing means disposedwithin said opening, a spur gear having a hub, said hub being securedwithin said bearing means, an elongated substantially hollow cylindricalmember extending through said opening and having an end thereof fixedlysecured to said hub, said cylindrical member being substantially hollowand being substantially open throughout its length to receive a penciltherein, said cylindrical member on the exterior end thereof having anoutwardly-extending substantially circumerential flange fixedly'securedthereto, a substantially cylindrical disc having a central apertureformed therein, said plate being mounted on said cylindrical member andhaving diametrically-opposed levers projecting laterally therefrom, asubstantially cylindrical casing fixedly secured to said top wall at thecircumferential marginal edge of said opening, said casing having a pairof diametricallyopposed axially-extending slots formed therein toreceive said levers therethrough, said casing having acentrallyapertured end wall at its upper end, a washer on saidcylindrical member, saidplate and said washer being disposed on oppositesides of said flange, a helicoidal spring surrounding said cylindricalmember and having an end thereof abutting against said Washer and itsother end abutting said hub, a plurality of bearings interposed betweensaid washer and said flange and said plate and said flange, andmotor-driven gear means mounted on said base and engaging with saidsecond gear.

4. A pencil sharpener as defined in claim 3, and brush means dependingfrom said top wall and disposed'in the P Of movement of said cylindricalmember.

5. A pencil sharpener as defined in claim 4, and brush means dependingfrom said top wall, said brush means being disposed in the path ofmovement of said cylindrical member and comprising a pair of confrontingbrushes, and means operable for movement of said cylindrical member inone direction against the tension of said spring to effect movement ofsaid brushes away from one another and to simultaneously energize saidmotor-driving means.

6. A pencil sharpener as defined in claim 5, and means for returningsaid brushes to their confronting positions when said last-named meanshas been rendered inoperative.

7. A pencil sharpener as defined in claim 6, and said top Wall having anopening extending transversely therethrough adjacent one of saidabrasive Wheels to permit the sharpening of leads on the upper abrasiveend thereof.

8. A pencil sharpener as defined in claim 7, and means cooperating withsaid last-named means to effect energization of said motor-drivingmeans.

References Cited by the Examiner UNITED STATES PATENTS 1,546,538 7/ 1925Fisher 12096 1,611,141 12/1926 Fisher 12096 2,179,140 11/1939 Theobald12096 2,615,427 10/ 1952 Liehmann 12096 2,664,071 12/1953 Guhc 120962,713,849 7/1955 Consentino 12094 X FOREIGN PATENTS 1,101,219 3/1961Germany.

EUGENE R. CAPOZIO, Primary Examiner. LAWRENCE CHARLES, Examiner.

1. A PENCIL SHARPENER COMPRISING A SUBSTANTIALLY HOLLOW RECTANGULARHOUSING HAVING A BASE WALL, OPPOSED TOP WALL, AND PAIRS OF OPPOSEDSIDEWALLS, SAID TOP WALL HAVING AN OPENING EXTENDING TRANSVERSELYTHERETHROUGH, BEARING MEANS DISPOSED WITHIN SAID OPENING, A SPUR GEARDISPOSED WITHIN SAID HOUSING ADJACENT SAID TOP WALL, SAID SPUR GEARHAVING A HUB JOURNALED FOR ROTATION IN SAID BEARINGS, AN ELONGATEDSUBSTANTIALLY HOLLOW CYLINDRICAL MEMBER HAVING AN END THEREOF FIXEDLYSECURED WITHIN SAID HUB FOR ROTATION THEREWITH, SAID CYLINDRICAL MEMBER,AT ITS OTHER END, HAVING A CENTRALLY-APERTURED CYLINDRICAL PLATEPROJECTING OUTWARDLY THEREFROM, SAID PLATE HAVING A PAIR OFOUTWARDLY-EXTENDING DIAMETRICALLY-OPPOSED LEVERS PROJECTING THEREFROM, AWASHER MOUNTED ON SAID CYLINDRICAL MEMBER, SAID PLATE AND WASHER BEINGDISPOSED ON OPPOSITE SIDES OF SAID FLANGE, A RESILIENT MEANS SURROUNDINGSAID CYLINDRICAL MEMBER AND BEARING AGAINS SAID WASHER AND SAID HUB,BEARINGS INTERPOSED BETWEEN SAID WASHER AND SAID FLANGE AND SAID PLATE,A SUBSTANTIALLY HOLLOW ELONGATED CYLINDRICAL CASING HAVING A PAIR OFOPPOSED OPEN AND CLOSED ENDS, MEANS CONNECTING SAID OPEN END OF SAIDCASING TO SAID TOP WALL AT THE CIRCUMFERENTIAL MARGINAL EDGE THEREOF,SAID CLOSED END OF SAID CASING HAVING A CENTRALLY-LOCATED APRETUREEXTENDING TRANSVERSELY THERETHROUGH, SAID CASING HAVING A PAIR OFAXIALLY-EXTENDING DIAMETRICLLY-OPPOSED SUBSTANTIALLY RECTANGULAR SLOTSFORMED THEREIN TO RECEIVE SAID LEVERS FOR RECIPROCATION, SAID LEVERSPROJECTING BEYOND THE SIDEWALL OF SAID CASING, A SHAFT MOUNTED ON SAIDBASE WALL, A SUBSTANIALLY HOLLOW ABRASIVE WHEEL MOUNTED ON SAID SHAFTFOR ROTATION THEREWITH, AND MEANS ENGAGING WITH SAID SPUR GEAR TO DRIVESAID ABRASIVE WHEEL AND SAID CYLINDRICAL MEMBER.